As to the first part of the proposition that this philosophical hypothesis has no primary recommendation either to reason or the imagination, we can soon satisfy ourselves with regard to reason, by the following reflections. The only existences of which we are certain are perceptions that, being immediately present to us in consciousness, command our strongest assent and are the ultimate basis of all our conclusions. The only conclusion we can draw from the existence of one thing to the existence of another is through the relation of cause and effect, showing that there is a connection between them and that the existence of one depends on that of the other. The idea of the cause-effect relation is derived from past experience in which we find that two ·kinds of· beings are constantly conjoined and are always present together to the mind. But no beings are ever present to the mind except perceptions; so we can observe a conjunction or cause-effect relation •between different perceptions, but can never observe it •between perceptions and objects. So it is impossible that from any fact about perceptions we can ever validly form any conclusion about the existence of objects ·when these are understood, as they are in the philosophical hypothesis, as different from perceptions·.
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